When a child under a certain age, as determined by law, travels in a motor vehicle, the child is required to be securely fastened within a child safety seat to prevent injury in the unfortunate, but occasional, vehicle accident. Child safety seats are designed, and in most instances required by law, to be positioned within the back seat of a motor vehicle. As a result, the child is substantially blocked from any direct air flow supplied by the vehicle's ventilation system by the seat backs of the front seats. In other instances the occupants of the front seat might not desire air flow, causing the air in the back of the car to become stagnated and undesirable for a child. Having a fan running near a sleeping infant was associated with a 72 percent decrease in the risk of sudden infant death syndrome, or SIDS, researchers reported in the Archives of Pediatrics and Adolescent Medicine. The study suggests that the fan use might reduce the risk for SIDS by decreasing rebreathing and increasing dispersion of carbon dioxide in the infant's airway. This may be advantageous for infants sleeping while traveling in a car as well. Furthermore, many children can become preoccupied by a rotating object, such as a fan, resulting in a more enjoyable ride for the older occupants of the vehicle.